Conventionally, telephone service wires from residences must be spliced to a main telephone cable, and such splicing is typically done where the ends of a service wire are collected loosely within a service box. The service box is typically buried to ground level. Typical service boxes are not waterproof, the covers typically being in the manner of conventional manhole covers which may be easily removed and which are just held in place by their weight. Water and other environmental elements typically foul the bottom of the service box where the service wires are left. When it is required to repair or otherwise attend at the service box to splice service wires to the main cable, it is very time consuming for a worker to have to disentangle the service wires fouled in the bottom of the service box, to determine which residential service wire needs attending to (as often the identifying tags or labels become dislodged) and to attempt to make a watertight seal around the splice before replacing the spliced ends back into the bottom of the service box.
It is known in the prior art to provide closeable housings to enclose the spliced ends of the service wire and main telephone cable, to keep the water from getting into the housing, see for example, U.S. Pat. No. 4,337,374. It is known in the prior art to fill such housings with grease and embed the spliced ends into the grease. Because, the grease breaks down, and, if the splice needs to be attended to, not only is it messy but the grease has to be repacked otherwise water will typically get into the housing, these prior art devices are not generally re-used but rather cut-off and thrown away if a splice needs to be re-done. Further, they are generally only considered water resistant rather than waterproof.
Other attempts in the prior art at providing a waterproof seal around spliced ends include the use of butyl tape to wrap around the spliced end.
It is also known in the prior art to provide racks within large manholes, for example, for mounting wires and the like. However, in the prior art it is neither taught nor suggested to provide racks within service boxes for releasable mounting thereto of watertight splice housings.
Applicant's invention is another useful improvement over the plethora of prior art devices, including those of Weagant (U.S. Pat. No. 3,395,382), Ruddell (U.S. Pat. No. 3,209,069), Caulkins (U.S. Pat. No. 3,951,503) and Roney (U.S. Pat. No. 5,347,084), which have attempted a solution to the vexing problem of providing re-usable water tight housings for wire splices.
Weagant, although superficially similar to the present invention as hereinafter described, teaches sealing legs 22 to conductors 10 by means of commercially available heat shrinkable material, whether or not legs 22 are made of such material or whether the heat shrinkable material is dimensioned to slide over the leg so that a conductor passes through the heat shrink sleeve and leg. Specifically, Weagant states starting in column 2, line 1:
The hermetic seal between the legs and the conductor passing therethrough is accomplished by use of heat shrinkable material. In one embodiment of the invention, the legs which are integral with the one cup-shaped member are made of heat shrinkable material while in another embodiment a sleeve of heat shrinkable material is dimensioned to slide over the leg and a conductor passing therethrough so that upon application of heat the sleeve will shrink onto the leg and conductor and seal the two together. PA1 The internal sizes of the individual cylindrical protrusions 30 are chosen to correspond to the most used standard cable diameters and, in order to provide as great a selection of cable diameters as possible, a number of sleeves are arranged one above the other to form stepped, projecting hollow cylinders, . . . when a cable has to be inserted into a base section 11 which is provided with these adapter sleeves or protrusions 30, one of the protrusions is cut through at the appropriate place, which corresponds to the diameter of the cable which is to be led into the base section and the cable is inserted through the opening thus formed. In this way a better correspondence between the size of the openings and the size of the cables fitted therein is usually obtained,
Weagant further teaches typically using a sealant such as a semi-thermal plastic sealant coated on the inside surface of legs 22. Upon application of heat the sealant softens and the legs shrink onto the conductors so that the sealant flows around the cable and partially out through the contracting ends of the legs forming a permanent mechanical seal (see column 3, lines 15-22). No other method of forming a seal is taught or suggested by Weagant.
For use within the housing, that is, not for use as a seal, Weagant teaches clamping the ends of conductors 10 using mating male and female conical friction clamp components 28 and 34. The clamp components bind the conductors between corresponding notches 30 and 36 in the clamp components 28 and 34. Cylindrical adapters 31 and 37 may be provided to improve the friction fit of the conductors being clamped in the notches. The adapters are located internally of the clamp components and thus do not contribute in any way to the sealing of the housing. The drawback of the Weagant method is that the sealing using heat shrinkable material requires the use of a heat source. To the best of Applicant's knowledge, the use of heat sources for example torches, is prohibited in the United States by many companies for use in confined areas such as man-holes or other underground boxes. However, the splicing which is the subject of the present invention is found in such confined areas. This prohibition is presumably is for safety reasons. Thus, the Weagant method of forming a seal is potentially removed from those methods available to a workman.
The disadvantage in having to use liquid sealing compounds is, as referred to by Ruddell et al. in column 3, line 11, among other things, that a user must wait while the sealing compound sets. A further disadvantage of sealing by welding is, among other things, the causing of noxious fumes and gases in an enclosed space such as in a service box which may pose a safety hazard. What is neither taught nor suggested, and what forms one of the distinguishing features of the present invention as further described below, is the use of the sliding mating of resilient sleeves to elongate tubular service wire receptacles so as to form a watertight seal around service wires without the need for liquid resin or welding or the use of heat shrinkable material requiring the use of a heat source. That is, the method of sealing of the present invention is a mechanical seal. The mechanical seal of the present invention, as it does not require a heat source, is neither taught nor suggested by the application of the Weagant teaching. Specifically, what is neither taught nor suggested, and what is an object of the present invention to provide is the use of resilient sleeves which are not heat shrinkable but rather slidably mountable to hollow cylindrical members such as hose barbs or tubes.
The mechanical sealing of the present invention is also neither taught nor suggested in the teaching of Ruddell et al. Rather than releasably sliding resilient sleeves so as to mount them to hollow cylindrical members as in the present invention, Ruddell et al disclose embedding a portion of the ends of cable to be joined in casting resin so as to secure the ends to the base section of the container in a water tight manner (column 1, lines 41-44). The base section of the container is closed at one end and apertures are made therein to permit the cables to be inserted into the container. The apertures are subsequently sealed by the casting resin (column 1, lines 60-64). Further, Ruddell et al teach that where one or several of the cables to be joined is polyethylene sheathed, the portion within the tube is preferably heated in an oxidizing flame (column 2, lines 70-726).
Ruddell et al disclose structures superficially resembling hose barbs, namely, adapter sleeves or protrusions 30 seen in FIGS. 4 and 5. Ruddell et al teach that, rather than protrusions 30 being hose barbs:
(column 3, lines 46-61).
Thus, although the cable is to be journalled through the opening in the protrusions 30, there is no suggestion of the use of a resilient sleeve as in the present invention, nor is there any requirement of such a resilient sleeve, Ruddell et al relying on the use of a casting resin to form a water tight seal, sometimes in conjunction with melting the polyethylene sheathing on the cable by the use of an oxidizing flame. The casting resin is a liquid casting resin poured into the base of the tube and allowed to set so as to seal the entry of the cable into the housing (column 3, lines 6-13). Once the resin sets, the joint enclosure is no longer reusable, for example if it is desired to add additional wires to a splice contained within the enclosure. It is also thus apparent that the protrusions 30 of Ruddell et al are not functionally akin to hose barbs such as used in the present invention in that it is neither taught nor suggested in any embodiment of the Ruddell device and method to slide a resilient sleeve over the outside of such a protrusion 30. In the present invention the resilient sleeve may be either slid over the hollow cylindrical member in the member in the manner of a hose barb, or slid into the hollow cylindrical member in the manner of a bushing, depending on the appropriate fit.
Thus it is within the ambit of the present invention for both sliding a resilient sleeve over the hollow cylindrical member and sliding the resilient sleeve into to hollow cylinder member so as to act as a resilient bushing.